Heart treatment apparatus and heart treatment method

Abstract

Precursor of fatal arrhythmia is detected and by setting the tolerance level for carrying out nerve stimulation depending on the severity degree of the precursor, significant variation of the heart rate is suppressed and induction of the fatal arrhythmia is repressed. For this purpose, precursor of tachyarrhythmia occurrence such as premature contraction, ST change, repolarization abnormality or the like is detected and the lower-limit of the atrium interval which becomes the tolerance level of the nerve stimulation is set according to the detected result. Then, it is constituted according to the precursor of aforesaid tachyarrhythmia such that time for making the nerve stimulation means in an operation state is to be adjusted or nerve stimulation is to be carried out as much as the heart rate of a predetermined number of times.

Description

TECHNICAL FIELD [0001] The present invention relates to a heart treatment apparatus for preventing occurrence of tachyarrhythmia by electrical stimulation of vagus nerve and more particularly relates to a heart treatment apparatus and a heart treatment method in which it is possible to control the electrical stimulation of the vagus nerve in response to precursor detection of the tachyarrhythmia occurrence. BACKGROUND ART [0002] In the past, there was proposed an apparatus having an object for preventing atrial fibrillation from being induced by the increase of the heart rate in which vagus nerve (fat pad) is stimulated if the spontaneous heart rate exceeds a predetermined threshold (see, for example, PCT Jap. laid-open patent publication H7-504596 [lower right column of page 3]). This fat pad exists by accompanying a sino-atrial node or an atrioventricular node and the fat pad relating to the sino-atrial node exists at a bended entrance of a right pulmonary vein and is positioned a...

AI Technical Summary

Benefits of technology

[0008] In view of aforesaid problems, the present invention has an object in which the heart rate is lowered and oxygen consumption of the heart muscle is reduced by controlling the vagus nerve stimulation in response to detection precursor of fatal arrhythmia such that the heart rate falls into a predetermined tolerance level and at the same time, correction of repolarization non-uniformity is attempted by suppressing heart rate variation and further, inducing of fatal arrhythmia is repressed by repressing the sympathetic nerve tension antagonistically owing to the vagus nerve stimulation.

[0018] According to the heart treatment apparatus and the heart treatment method of the present invention, tolerance level of heart activity is set in response to precursor detection of tachyarrhythmia occurrence and it is possible to carry out nerve stimulation such that the heart activity is maintained within the tolerance level, so that it is possible to optimize electrical instability of the ventricle after the precursor for a patient of an organic heart disease such as myocardial infarction or cardiomyopathy and to suppress occurrence of fatal arrhythmia.

[0019] Also, tolerance level of the heart activity and stimulation time of the vagus nerve is controlled by comprehensively observing kinds of detected precursors and results of measured heart activities, so that treatment by the vagus nerve stimulation is never carried out excessively and consequently, it is possible to suppress limitation of a patient's exercise capability to be small.

Problems solved by technology

However, there is a case in which a serious heart damage occurs by other factors even in a case when the heart rate is not high.

Consequently, there is a possibility in the apparatus described in the Patent Reference 1 that a fatal arrhythmia which cannot be prevented may occur.

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